Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
11
pubmed:dateCreated
1985-12-18
pubmed:abstractText
It is suggested that the antipsychotic efficacy of opioids in patients suffering from schizophrenia may result from an interaction of opioids with the dopaminergic system. The modulatory effect of opioids on dopaminergic functions has already been demonstrated in basic experiments: Anatomical and biochemical data reveal an interaction between opioid receptors and dopamine (DA) actions on dopaminergic nerve terminals, cell bodies, and afferent nerve endings. Endogenous enkephalin levels correlate well with the endogenous dopamine content in various brain areas. Systemic or iontophoretic administration of morphine alters the spontaneous activity of ventral tegmental dopaminergic neurons. Morphine and enkephalin effectively enhance pituitary prolactin release, whereas dopamine inhibits it. Opioid agonists effectively alter DA release, DA reuptake, and DA metabolism in the striatum and substantia nigra. In reverse, chronic neuroleptic treatment enhances the synthesis and release of pituitary beta-endorphin. Opioids affect contralateral rotation elicited by dopamine agonists in animals with unilateral lesions of the nigrostriatal pathway. Phencyclidine, a psychotropic drug that shares certain pharmacological characteristics with the putative sigma-opioid receptor ligand SKF 10,047, indirectly mimics the effects of dopamine agonists on prolactin release, release of acetylcholine, etc. It is suggested that an imbalance of opiate-DA interaction might be involved in the pathogenesis of schizophrenia. Consequently, clinical studies on the effects of opioids on psychotic symptoms should also examine opioid influence on dopaminergic functions in these patients.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Nov
pubmed:issn
0006-3223
pubmed:author
pubmed:issnType
Print
pubmed:volume
20
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1211-31
pubmed:dateRevised
2004-11-17
pubmed:meshHeading
pubmed:year
1985
pubmed:articleTitle
Dopamine and the action of opiates: a reevaluation of the dopamine hypothesis of schizophrenia. With special consideration of the role of endogenous opioids in the pathogenesis of schizophrenia.
pubmed:publicationType
Journal Article, Review